Thin film recording head with a buried coil providing a shortened yoke and improved dimension control

ABSTRACT

A writer for magnetic recording heads. The writer includes a bottom magnetic pole and a write gap formed over the bottom pole and a coil trench formed in the bottom pole. A top magnetic pole is provided as two layers with the first layer including front and back tips with spaced apart walls positioned adjacent the trench bottom defining trench sides. A pole cover layer is included that is made up of a thin layer of insulating material deposited to cover the sides and bottom of the coil trench. A bottom coil is formed on the pole cover layer in the bottom of the coil trench and coil insulation is provided between the coil elements and adjacent the trench walls and covering the coil. A top coil with insulation is formed over the planarized bottom coil insulation and the top pole second layer is formed over the top coil.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to the field of magneticread/write heads and magnetic data storage, and more particularly, to athin film write head, and method of making such head, including aseparator layer of insulating material providing a cover over front andback tips of the top pole to reduce the separation distance between thebottom coil turns and the front and back pole tips which reduces theyoke length.

2. Relevant Background

Data is stored on magnetic media by writing on the magnetic media usinga write head. Magnetic media can be formed in any number of ways, suchas tape, floppy diskette, and hard disk. Writing involves storing a databit by utilizing magnetic flux to set the magnetic moment of aparticular area on the magnetic media. The state of the magnetic momentis later read, using a read head, to retrieve the stored information.Data density is determined by the amount of data stored on an area ofmagnetic media and depends on how much area must be allocated to eachbit. Data on magnetic media is often stored in a line or track. Magneticmedia often have multiple tracks. In the case of disks, the tracks arenested annular rings with more bits per track and more tracks per diskincreasing data density. Data density or areal density, therefore, isdetermined by both the bit length and by the width of the bit. Todecrease bit size, head size is decreased by fabricating thin film readand write heads.

Ongoing, important goals of researchers in magnetic recording technologyinclude producing disk drive read heads that achieve strong signals,providing accurate read back of those signals, minimizing noiseinterference, and providing very high areal density while controllingmanufacturing costs. Unfortunately, some of these goals directlyconflict with one another. For example, to achieve ever-higher arealdensities, track widths on a disk become smaller necessitating that thecomponents used to read and write data also become smaller, which makesmanufacturing more difficult and expensive.

Generally, the writer element of a thin film head is fabricated usingtop and bottom magnetic pole pieces and a multi-turn coil, which iswound between the top and bottom poles. The coil is defined on top ofthe lower pole prior to the formation of the upper pole. FIG. 1illustrates one exemplary prior art read/write head fabricated as aconventional composite-type thin film magnetic head, and the followingis a brief description of typically head manufacturing steps of such ahead. The composite type thin film magnetic head in this embodiment hasa reading GMR reproducing element on a substrate and a writing inductivetype thin film magnetic head stacked on the reading element. Since inpractically manufacturing a thin film magnetic head, many thin filmmagnetic heads are formed on a wafer at the same time, the end of eachthin film magnetic head is not shown.

An insulating layer 2, e.g., alumina, is formed in a thickness of about1 to 5 μm on a substrate 1, e.g., AlTiC, on which a first magnetic layer3 constituting one magnetic shield layer to protect the reading GMRelement from an external magnetic field is formed in a thickness of 2–3μm. Then, a first shield gap layer 4 is sputter formed of an insulatingmaterial, e.g., alumina, in a thickness of about 50–150 nm, andthereafter a multilayered structure-magnetoresistive layer 5constituting the GMR reproducing element is formed such as at athickness of less than 100 nm. For forming the magnetoresistive layer 5into a desired pattern, a photoresist layer is formed on the layer 5.The photoresist layer can be formed in a shape for easy lift off, forexample, a T-shape. Next, the magnetoresistive layer 5 is ion-milledthrough the photoresist film as a mask, and thereby is formed in adesired pattern. Then, a second shield gap film 8, e.g., alumina, isformed in a thickness of 50–150 nm to embed the magnetoresistive layer 5into the first and second shield gap layers 4, 8, and a second magneticlayer 9, e.g., permalloy, is formed in a thickness of 2–6 μm. The secondmagnetic layer 9 works not only to magnetically shield the GMRreproducing element along with the magnetic layer 3, but also as thebottom pole in the thin film recording head.

A write gap layer 10 made of nonmagnetic material, e.g., alumina, isformed in a thickness of about 50–300 nm on the second magnetic layer 9and thereafter an insulating layer 11 made of photoresist is formed in athickness of 0.5–2 μm corresponding to a given pattern. Then, a firstlayer, thin film coil 12 is formed, such as in a thickness of 3 μm, witha photoresist film 13 providing insulation separation from the top pole16. The insulating layer 13 made of photoresist to cover the firstlayer-thin film coil 12 is typically flattened by a thermal treatment,and a second layer-thin film coil 14 is formed, such as in a thicknessof 3 μm, so as to be insulation separated by and also supported by aninsulating layer 15 made of photoresist. The insulating layer 15 made ofphotoresist to cover the second layer-thin film coil 14 is flattened bya thermal treatment, and thereafter, a third magnetic layer or top pole16 is formed corresponding to a given pattern and is typically made of apermalloy material or FeN material having a high saturated magnetic fluxdensity.

Fabrication of the head shown in FIG. 1 has presented a number ofchallenges and sometimes less than desirable results. The coil element12 is insulated from the front and back (or adjacent) pieces of the toppole 16 by cured photoresist 13, and to achieve desired insulationresults, the final dimensions of this photoresist insulation 13 must becarefully controlled to insure that it is thick enough to not onlyeffectively insulate the coil turns 12 but to also endure subsequentmanufacturing processes without erosion that would expose the coil 12(i.e., fail to adequately insulate the bottom coil 12 from the top coil14 or the top pole 16). As a result, prior art heads have generally beenfabricated with a relatively large thickness of photoresist between theend turns of the bottom coil 12 and the adjacent front and back piecesof the top pole 16, as shown by the separation distance, dSEp, inFIG. 1. Additionally, the slope (as shown at 17) of the cured resistinsulator 13 must be controlled within exacting limits to allowformation of the top pole 16 by photolithography. These two limitationsresult in extended processing times to properly cure the resistinsulator 13. Further, the top pole 16 has an undesirably large yokelength, L_(YOKE), to accommodate the larger coil and insulator stacks.Head fabrication is further complicated because photolithography of thetop pole 16 must be performed on surfaces with substantial topographyand large step heights that can result in ineffective control of thedimensions of the elements of the produced head.

Hence, there remains a need for a thin film write head and correspondingmanufacturing processes that support the need for tight dimensioncontrols and adequate insulation between coils and pole elements whilereducing fabrication complexity, processing times, and costs andfurthering head design goals such as reduced pole length.

SUMMARY OF THE INVENTION

The present invention addresses the above problems by providing a writerfor use in write heads and read/write heads that is configured toprovide a reduce separation distance between bottom coil elements andthe top pole. The design of the writer reduces processing times andcosts while also enhancing dimensional control of the writerfabrication. Briefly, the writer of the invention includes a bottommagnetic pole with a planar upper surface in which material is removedto form a recessed area that defines a bottom of a coil trench. A writegap layer is formed over the upper surface of the bottom pole andextends at least partially over the bottom of the coil trench. Thewriter further includes a top magnetic pole that is formed as twolayers. The first layer includes a front pole tip and a back pole tipthat each include an interior side wall that is substantially vertical(e.g., perpendicular to the upper surface of the bottom pole), spacedapart, and positioned adjacent the bottom of the coil trench to definethe sides of the coil trench.

Significantly, the writer further includes a pole cover layer orpole-coil separator made up of a thin, e.g., less than 0.5 micrometersand more typically 0.1 to 0.4 micrometers in thickness, of insulatingmaterial such as alumina. The pole cover layer is deposited so as tocover at least the sides of the coil trench (i.e., the interior sides ofthe pole tips) and the bottom of the coil trench including write gapmaterial deposited on the bottom of the coil trench. A bottom coil isthen formed directly on the pole cover layer in the bottom of the coiltrench and coil insulation is provided between the coil elements andadjacent the side walls and to cover the coil elements. In oneembodiment, the coil insulation is provided in two layers of the same ordiffering materials. A planarized surface is provided for supporting atop coil and includes coplanar upper surfaces of the pole tips, ends ofthe pole cover layer, and the bottom coil insulation. The writer elementincludes the top coil, along with its insulation, which is formed on theplanarized surface of the bottom coil insulation. The second layer ofthe top pole is formed over the top coil so as to contact the front andback pole tips and defines the yoke region of the writer.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional view of a magnetic read/write head with aconventional writer element configuration;

FIG. 2 illustrates a data storage and retrieval apparatus in which awriter element structure according of the present invention may beimplemented, such as in a merged read/write head or other type of thinfilm magnetic recording head;

FIG. 3 is a sectional view of recording head (or writer element)constructed according to the present invention with a buried bottom coilin a trench defined by front and back pieces of the top pole; and

FIG. 4 is flow chart providing exemplary manufacturing steps of a headfabrication process according to the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention is directed toward a buried coil write elementdesign for reducing separation distances between coils and pole elementsin magnetic recording heads, toward write heads or read/write headsincluding the buried coil design (i.e., including a magneticallyseparating cover layer), toward methods of making a recording headaccording to the invention with improved dimensional control, and towardmerged read/write heads and storage systems that incorporate buried coildesigns as described herein. The write heads of the present inventioninclude a buried bottom coil element that is fabricated after theformation of the front and back magnetic pole tips of the top pole. Thefront and back pole tips define a trench or recessed area in which apole cover layer or pole-coil separator is provided of a non-magneticmaterial, such as alumina, and then the bottom coil is built directly onthis cover layer or separator. A coil insulator is provided within thetrench to separate the bottom coil turns and to cover the turns (i.e.,to electrically insulate the bottom coil from the top coil), and thecoil insulator can then be planarized to facilitate fabrication of thetop coil, top coil insulator, and top pole yoke.

The “buried” bottom coil design of writer elements and heads of thepresent invention provides a number of advantages and/or addresses anumber of problems with prior art heads. Because the bottom coil sitsdirectly on the alumina or other nonmagnetic material of the cover layeror separator, there is no need for an underlying resist or insulationlayer. The cover layer or separator allows bottom coils to be positionedin relatively close proximity to adjacent front and back tips of the toppole, i.e., to provide a head with a reduced coil-pole separationdistance and a reduced yoke length relative to convention heads. Thebottom coil is planarized using photoresist or another insulatingmaterial that may be vacuum deposited or otherwise deposited among andover the bottom coil as a single process with one material or in twoprocesses involving a single material or two insulating materials. Theuse of a deposited pole cover layer and coil insulator results insignificantly reduced processing times, e.g., by reducing or eveneliminating cure times and facilitating building of the top coil and toppole yoke element. Additionally, the forming of the front and back toppole tips (such as by photolithography) is unaffected by the bottom andtop coil geometries.

FIG. 2 shows a typical disk type magnetic data storage and retrievalapparatus 100 in which embodiments of the writer element of theinvention may be incorporated. The writer element with a buried bottomcoil of the present invention is located within a merged read/write headassembly 120 that rides above a magnetic storage media 110, depicted inFIG. 2 as a rotatable hard disk type storage media. The hard disk 110 iscoupled to a motor 140 via a spindle 150 to provide rotation of the disk110 relative to the head assembly 120. An actuating device 130 may beused to position the head assembly 120 above the surface of the media110 to read and write data in the form of magnetic bits from and to themedia 110. Of course, the data storage and retrieval apparatus 100typically has several hard disks 110 and several corresponding headassemblies 120, not shown here for ease of description. The read portionof the read/write head assembly 120 is not limiting to the invention andits configuration may vary significantly to practice the invention aslong as the read element is combined with a buried coil recording heador writer element as described below. Further, in some cases, a writehead may be provided without a read sensor and the apparatus 100 wouldsimply substitute such a write or recording head constructed accordingto the invention for the read/write head assembly 120.

With reference to FIG. 3, the present invention is shown embodied in awrite element 200 that can be incorporated within a recording head or ina merged read/write head. The head 200 terminates at front edge orsurface (i.e., the left end of the head 200 shown in FIG. 3) thatdefines an air bearing surface (ABS) for the head 200. If utilizedwithin a read/write head, the bottom pole comprising layers 210, 212would act as a second shield of the read portion. The read portiontypically would be built on a ceramic substrate and include first andsecond shields formed adjacent one another with a layer of dielectricmaterial sandwiched between the shields. The shields are typicallyformed of a soft magnetic alloy, such as NiFe alloy, CoNiFe alloy,CoZrNb alloy, and the like. A read sensor would then be embedded withinthe dielectric material layer adjacent the ABS of the head 200.

As shown in FIG. 3, the writer element 200 includes a first or bottompole that can be formed of a single layer or as shown, of two layers,i.e., a lower film 210 upon which a second layer 212 with a seed layer214 is deposited (such as by sputtering). The bottom pole layers 210,212 may be fabricated of a number of magnetic materials such as NiFealloy, CoNiFe alloy, CoZrNb alloy and other soft magnetic alloys ormaterials with the seed layer 214 being CoNiFe, CoFeN, or other highmoment magnetic materials and the material used in the layers 210, 212may be the same magnetic material or be a different magnetic material.Significantly, a trench or recessed area 216 is defined (at least inpart) by the removal such as by etching of a portion of the bottom pole,such as by removal of a portion of the hot seed layer 214 and, in somecases, a portion of the second layer 212 of the bottom pole. The lengthof the trench 216 defined by the material removed from the bottom poleis typically less than the yoke length, L_(YOKE), but greater than orequal to the bottom combined width of the bottom coils 244. As willbecome clear, the trench 216 is useful for allowing electricalinsulation and magnetic separation materials to be deposited and abottom coil to be “buried” in the trench 216 to facilitate more rapidand dimensionally accurate fabrication of the element 200.

The write element 200 further includes a write gap layer 220 ofnonmagnetic or dielectric material that is deposited at least over thefront portion of the bottom pole, i.e., over the front piece of the seedlayer 214, and more preferably, deposited so as to extend oversubstantially the length of the bottom of the trench 216, i.e., to theback piece of the seed layer 214. A first insulator 224 formed of a filmof electrically insulating material, e.g., alumina and the like, ispositioned on top of an interior portion of the write gap layer 220 todefine the throat height and to provide an inner edge defining a portionof the trench 216 side wall.

The top pole shown can be thought of as a two layer or bi-layerconstruction or pole layers P2 and P3 that includes back and front poletips 236, 238 and an upper pole layer or yoke layer 270. By fabricatingthe top pole with two layers, the bottom coil 244 can be buried withinthe trench 216 defined in part by the interior side walls of the poletips 236, 238 and then the top coil 260 and yoke layer 270 can bereadily built on a planarized surface (i.e., a surface with minimaltopography). The first layer P2 of the top pole includes a back pole tip236 built upon a seed layer 230 and a front pole tip 238 built upon aseed layer 232 (which overlays the write gap layer 220 near the ABS ofthe element 200 and the first insulator 224). The pole tips 236, 238 areformed of a magnetic material such as CoNiFe alloy, NiFe alloy (i.e.,permalloy), and the like. As will be explained with reference to FIG. 4,the pole tips 236, 238 and underlying seed layers 230, 232 are typicallyformed by material deposition and then later removal of material toprovide substantially vertical interior side walls that define the sidesof the trench 216 (although some slope can be provided if useful tosupport the material removal process).

According to an important aspect of the invention, the write element 200includes a pole tip cover layer or pole-coil separator 240 that isdeposited within the trench 216. The pole-coil separator 240 functionsto insulate the pole tips 236, 238 from the adjacent bottom coils 244,and as such is typically made of alumina or other insulating material.The bottom coil 244 is then formed to sit directly on the pole-coilseparator 240 and with a second insulator 12 being provide among andover the coils 244 to further separate the coils 244 from the pole tips236, 238 and to electrically insulate (e.g., formed of alumina ormaterial with similar electrical properties) the bottom coils 244 fromthe top coils 260.

In the embodiment shown in FIG. 3, the second insulator or bottom coilinsulator 12 is formed of two layers, i.e., a lower or coil layer 250that is deposited after formation of the coils 244 to insulate theindividual coil turns in the bottom coil 244 and to further insulate theouter coils in the bottom coil 244 from the pole tips 236, 238 and anupper or cover layer 254 for insulating the bottom coil 244 from the topcoil 260 and providing a surface for building the top coil 260. Thecoils 244 are preferably thin with a thickness in one embodiment of lessthan 2 μm. The use of two layers 250, 254 facilitates more rapid andaccurate fabrication of the element 200, and the materials used for thelayers 250, 254 may be the same or, more typically, the materials usedare different but that provide desired insulating and fabricationproperties. The bottom or lower coil layer 250 can be photoresist oralumina or other similar material. In one preferred embodiment, thebottom coil layer 250 is photoresist and the top layer 254 is alumina tofacilitate processing, such as by reducing cycle time and better suitingequipment availability.

Significantly, the cover layer or pole-coil separator 240 can berelatively thin, e.g., less than 0.5 μm and more preferably between 0.1and 0.4 μm, in part because it is deposited directly within the trench216 and upon the high density alumina film or write gap layer 220. Thisvery thin pole cover layer 240 when combined with the coil insulatorlayer 250 provides a significantly reduced front and rear separationdistance, d_(SEP1) and d_(SEP2), between the coils 244 and the adjacentpole tips 238 and 236, respectively. For example, the front and rearseparation distances, d_(SEP1) and d_(SEP2), typically can be achievedin the range of about 1 to 2 μm whereas prior heads typically hadseparation distances of at least about 3 μm. With the buried coil 244within the trench 216 that is covered by cover layer 240, the topsurface of the pole tips 236, 238 and the filled trench materials (i.e.,cover layer 240 sides and cover insulator layer 254) can be processed toprovide a desired surface for building the other components of the writeelement 200, such as with planarization.

The writer 200 further includes a top coil 260 that, as with bottom coil244, is typically formed of copper or similar material, and that ispositioned on the cover insulator layer 254. A third insulator or topcoil insulator 13 is formed among and over the top coils as shown at 264and is formed, for example, of alumina. The top pole further includes anupper pole layer or yoke layer 270, formed of material the same orsimilar to that used for the pole tips 236, 238, that covers andcontacts at least a portion of the front pole tip 238 and covers the topcoil 260 and back pole tip 236. The yoke length, L_(YOKE), of the toppole is significantly reduced compared with convention writer elementsbecause of the reduced the reduced pole-coil separation distances,d_(SEP1) and d_(SEP2), provided by the thin pole cover layer 240 andburied bottom coil 244.

FIG. 4 illustrates an exemplary fabrication process 300 for creatingwrite elements, such as element 200, of the invention. As discussedpreviously, the inventive features of the write elements can be providedalone within a head but more typically are provided in a mergedread/write head. Because the read element portion of heads fabricatedare not limiting to the invention, the manufacturing process 300 isdiscussed as starting at 310 with the provision of a substrate forfabricating a bottom pole but the bottom pole could just as easily andtypically will provide the second shield of a read element.Additionally, the material deposition, layer formation, and materialremoval steps described in process 300 described with reference to thehead or element 200 without illustrations being provided for each layerformation and then material removal as it is believed that theseprocesses will be readily understood by those skilled art.

At 316, the bottom pole P1 is formed including creating a recessedsurface, i.e., the bottom of the trench 216 for later deposition of thepole cover layer 240. The bottom pole P1 is typically formed by platinga first material layer 210 and then defining the shape of the layer 210such as with chemical mechanical polishing (CMP). A second materiallayer 212 is deposited on the first material layer 210 such as bysputtering a magnetic film, e.g., a film of NiFe or the like. A seedlayer 214 is then provided on the second material layer 212 and thebottom surface of the trench 216 is formed by removing material from thebottom pole, such as by ion beam etching or other processes. At 320, adeposition of metal, such as NiCr, is performed to form the write gap220, with a photoresist mask first being provided and lift off beingused to provide the desired shape of the write gap 220.

At 324, the front pole insulator 224 is formed of insulating material.At 330, the lower layer P2 of top pole is formed using seed layer 230,232 followed by deposition of a magnetic material, such as CoNiFe andthe like, which is then partially etched to form the front pole tip 238and the back pole tip 236. The etching or other material removal processis performed in a manner that defines substantially vertical inner sidewalls that define the sides of the trench 216, in which the bottom coil244 is later “buried.” The pole tips 236, 238 are preferably shaped todefine the track width of the writer element 200.

At 340, a thin, e.g., 0.1 to 0.4 μm, layer of insulating material, suchas alumina, is deposited over the pole tips 236, 238 and within thetrench 216 to form the pole cover layer or pole-coil separator 240.Connections to the pole tips 236, 238 may be created during step 354 byCMP or otherwise removing a portion(s) of the pole cover layer 240. Aswill be appreciated, the deposition of the coil cover 240 rather thancuring layers of photoresist results in a much quicker process, athinner separation distance between the coils 244 and pole tips 236,238, and facilitates later formation of the bottom coil 244.

In this regard, the coil 244 is next formed at 350 such as with copperor other conducting material that is preferably thin, e.g., less thanabout 2 μm, directly upon the deposited pole-coil insulator or polecover layer 240. Also, at 350, the second insulator I2 is formed bycoating the pole-coil insulator 240 (and, in some cases, a portion ofthe coils 244) with a layer of insulating material, such as alumina, toform the coil insulating layer 250 and then second depositing anotherlayer of insulating material over the coil insulating layer 250 andcoils 244 to fill the trench 216 (i.e., bury the coils 244) and form thecovering insulation layer 254. In some preferred embodiments, theinsulating material used for the two portions of the second insulator 12are formed of differing materials to create a bi-material bottom coilinsulator 12 such as any two compatible photoresist materials and/orvacuum deposited insulating materials.

At 354, the pole tips 236, 238, the pole-coil insulator 240, and thecovering insulation layer 354 are planarized (such as with CMP) toprovide a desirable (i.e., planar) surface for building the top coil 250and yoke region of the top pole 270. Additionally, such planarizationprovides enhanced dimension control. At 360, the top coil 260, such as afilm of copper, is formed, such as by plating, on the now planarcovering insulation layer 254. A third insulator 13 is formed as shownat 264, such as of deposited photoresist. At 370, the top pole yokelayer 270 is formed, such as by sputtering a thin film of NiFe or othermagnetic material, and this layer 270 is preferably kept relatively thinto decrease the size of the element 200, such as with a thickness lessthan 3 μm and more preferably in the range of 1 to 3 μm. As explainedabove the yoke length, L_(YOKE), is significantly shorted relative toconventional writer elements due to the use of the pole cover layer 240and buried coil design. At 380, additional processing steps arepreformed to complete the writer element 200 such as with forming aconnection pad, such as of copper, gold, and/or other conductors, anddeposition of an overcoat (not shown), such as a layer of alumina orother insulator. As a result of the design of the head 200 and the aboveprocessing 300, the yoke length, L_(YOKE), is typically achievable inthe range of about 9 to 11 μm, which is a large improvement over priorhead designs that had yokes with lengths in the range of 12 to 17 μm ormore.

Although the invention has been described and illustrated with a certaindegree of particularity, it is understood that the present disclosurehas been made only by way of example, and that numerous changes in thecombination and arrangement of parts can be resorted to by those skilledin the art without departing from the spirit and scope of the invention,as hereinafter claimed. For example, the specific materials describedabove can be varied significantly to practice the invention as will bereadily appreciated by those skilled in the art.

1. A writer for use in a data recording head assembly, comprising: abottom magnetic pole having a substantially planar upper surfaceincluding a recessed surface defining a bottom of a coil trench; a writegap layer deposited on the upper surface of the bottom magnetic poleextending to cover and contact at least a portion of the recessedsurface; a top magnetic pole disposed above the bottom magnetic pole andthe write gap layer including a first layer comprising a front pole tipand a back pole tip spaced apart with side walls defining side walls ofthe coil trench, wherein the pole tips each include an upper surfacedistal to the bottom magnetic pole with the upper surfaces beingsubstantially coplanar; a pole cover layer of insulating materialdisposed with a thickness over the recessed surface of the bottommagnetic pole and over the side walls of the top pole tips, the polecover layer contacting and covering a portion of the write gap layerextending to cover and contact the portion of the recessed surface; anelectrically conducting coil with elements disposed on the pole coverlayer between the top pole tips; and an insulator covering the coil andfilling gaps between the coil elements and the top pole tips, whereinthe insulator comprises a coil insulator layer disposed among the coilelements and covering the side walls of the pole tips and a coveringinsulation layer disposed over the coil insulator layer and the coils.2. The writer of claim 1, wherein the thickness of the pole cover layeris less than about 0.5 micrometers.
 3. The writer of claim 1, whereinthe insulating material of the pole cover layer is provided by materialdeposition.
 4. The writer of claim 1, wherein the covering insulationlayer includes an upper surface distal to the coil elements that issubstantially planar and substantially coplanar with the upper surfacesof the pole tips.
 5. The writer of claim 1, wherein the coil insulatorlayer is formed of a first insulating material and the coveringinsulation layer is formed of a second insulating material that differsfrom the first insulating material.
 6. The writer of claim 1, whereinthe write gap layer extends to cover and contact substantially all ofthe recessed surface of the bottom magnetic pole.
 7. The writer of claim1, wherein a separation distance measured between a proximal portion ofthe coil and the front pole tip is between about 1 micrometer and about2 micrometers.
 8. A writer for use in a data recording head assembly,comprising: a bottom magnetic pole having a substantially planar uppersurface including a recessed surface defining a bottom of a coil trench;a write gap layer deposited on the upper surface of the bottom magneticpole extending to cover and contact at least a portion of the recessedsurface; a top magnetic pole disposed above the bottom magnetic pole andthe write gap layer including a first layer comprising a front pole tipand a back pole tip spaced apart with side walls defining side walls ofthe coil trench, wherein the pole tips each include an upper surfacedistal to the bottom magnetic pole with the upper surfaces beingsubstantially coplanar; a pole cover layer of insulating materialdisposed with a thickness over the recessed surface of the bottommagnetic pole and over the side walls of the top pole tips, the polecover layer contacting and covering a portion of the write gap layerextending to cover and contact the portion of the recessed surface; anelectrically conducting coil with elements disposed on the pole coverlayer between the top pole tips; and an insulator covering the coil andfilling gaps between the coil elements and the top pole tips, whereinthe top magnetic pole includes a second layer of magnetic materialdefining a yoke region above the defined coil trench and includes a topelectrically conducting coil with elements disposed on the insulator,the top coil elements being electrically insulated by a top coilinsulator formed of electrically insulating material disposed over thetop coil elements and the insulator.
 9. A system for storing andretrieving digital data to and from a magnetic recording media,comprising: a head assembly positionable adjacent the magnetic recordingmedia comprising: a read head; and a write head comprising: a bottommagnetic pole having a recessed surface defining a bottom of a coiltrench; a write gap layer deposited on the upper surface of firstmagnetic pole extending to contact at least a portion of the bottom ofthe coil trench; a top magnetic pole disposed above the first magneticpole and the write gap layer including a first layer comprising a frontpole tip and a back pole tip spaced apart with side walls defining sidewalls of the coil trench, wherein the pole tips each include an uppersurface distal to the first magnetic pole with the upper surfaces beingsubstantially coplanar; a pole-coil separator disposed over the recessedsurface of the bottom magnetic pole and over the side walls of the toppole tips, the pole-coil separator contacting an upper surface of thewrite gap layer contacting the portion of the bottom of the coil trench;an electrically conducting coil with elements disposed on the pole-coilseparator between the top pole tips; and an insulator covering the coiland filling gaps between the coil elements and the top pole tips; and adrive device for coupling to the media so as to move the media withrespect to the head assembly, wherein the insulator comprises a coilinsulator layer disposed among the coil elements and covering the sidewalls of the pole tips and a covering insulation layer disposed over thecoil insulator layer and the coils.
 10. The system of claim 9, whereinthe wherein the pole-coil separator has a thickness of less than about0.5 micrometers.
 11. The system of claim 9, wherein the pole-coilseparator comprises a layer of deposited insulating material.
 12. Thesystem of claim 9, wherein the covering insulation layer includes anupper surface distal to the coil elements that is substantially planarand substantially coplanar with the upper surfaces of the pole tips. 13.The system of claim 9, wherein the coil insulator layer is formed of afirst insulating material and the covering insulation layer is formed ofa second insulating material that differs from the first insulatingmaterial.
 14. A system for storing and retrieving digital data to andfrom a magnetic recording media, comprising: a head assemblypositionable adjacent the magnetic recording media comprising: a readhead; and a write head comprising: a bottom magnetic pole having arecessed surface defining a bottom of a coil trench; a write gap layerdeposited on the upper surface of first magnetic pole extending tocontact at least a portion of the bottom of the coil trench; a topmagnetic pole disposed above the first magnetic pole and the write gaplayer including a first layer comprising a front pole tip and a backpole tip spaced apart with side walls defining side walls of the coiltrench, wherein the pole tips each include an upper surface distal tothe first magnetic pole with the upper surfaces being substantiallycoplanar; a pole-coil separator disposed over the recessed surface ofthe bottom magnetic pole and over the side walls of the top pole tips,the pole-coil separator contacting an upper surface of the write gaplayer contacting the portion of the bottom of the coil trench; anelectrically conducting coil with elements disposed on the pole-coilseparator between the top pole tips; and an insulator covering the coiland filling gaps between the coil elements and the top pole tips; and adrive device for coupling to the media so as to move the media withrespect to the head assembly, wherein the top magnetic pole includes asecond layer of magnetic material defining a yoke region above thedefined coil trench and includes a top electrically conducting coil withelements disposed on the insulator cover, the top coil elements beingelectrically insulated by a top coil insulator formed of electricallyinsulating material disposed over the top coil elements and theinsulator.
 15. A writer for use in a data recording head assembly,comprising: a bottom magnetic pole having a substantially planar uppersurface including a recessed surface defining a bottom of a coil trench;a write gap layer deposited on the upper surface of the bottom magneticpole; a top magnetic pole disposed above the bottom magnetic pole andthe write gap layer including a first layer comprising a front pole tipand a back pole tip spaced apart with side walls defining side walls ofthe coil trench, wherein the pole tips each include an upper surfacedistal to the bottom magnetic pole with the upper surfaces beingsubstantially coplanar; a pole cover layer of insulating materialdisposed with a thickness over the recessed surface of the bottommagnetic pole and over the side walls of the top pole tips, the polecover layer contacting and covering a portion of the write gap layerextending to cover and contact a portion of the recessed surface; anelectrically conducting coil with elements disposed on the pole coverlayer between the top pole tips; and an insulator covering the coil andfilling gaps between the coil elements and the top pole tips, whereinthe insulator comprises a coil insulator layer disposed among the coilelements and covering the side walls of the pole tips and a coveringinsulation layer disposed over the coil insulator layer and the coils;and wherein the coil insulator layer is formed of a first insulatingmaterial and the covering insulator layer is formed of a secondinsulating material that differs from the first insulating material. 16.The writer of claim 15, wherein the covering insulator layer includes anupper surface distal to the coil elements that is substantially planarand substantially coplanar with the upper surfaces of the pole tips.